By Mohamed Sudam and Scott DiSavino
SANAA/NEW YORK (Reuters) - Yemen said on Friday it was holding a U.S. citizen suspected of being an al Qaeda militant who killed a hospital guard last week, and a U.S. firm said the suspect had worked at nuclear reactors in New Jersey.
Sharif Mobley was among 11 al Qaeda suspects arrested in the Yemeni capital in early March, a Yemeni government source told Reuters. Another Yemen official said authorities had "unconfirmed suspicions" he had links to a Nigerian man who was behind a December 25 bomb attempt on a U.S.-bound plane.
A U.S. company which owns several nuclear power plants said Mobley, 26, worked at the Salem and Hope Creek nuclear reactors in New Jersey and other reactors in the area.
The company, Public Service Enterprise Group Inc, said in a report to the U.S. Nuclear Regulatory Commission that Mobley worked as a laborer from 2002 to 2008, mainly during refueling outages for several weeks at a time.
He did routine labor work carrying supplies and assisting maintenance activities. U.S. officials were in the process of reviewing his activities in the United States, one law enforcement official said.
"At this time, we are not aware of any security-related concerns or incidents related to Mr. Mobley's employment at these locations. However we continue to review his past activities," said the official, who did not want to be named.
The official said that the U.S. government had been aware of him "for some time."
The Yemeni government source told Reuters that Mobley was the al Qaeda suspect who started a gunbattle at a hospital in Sanaa last week in a bid to escape detention.
He was recaptured, but not before killing one person and wounding several others.
IN YEMEN FOR AT LEAST A YEAR
Yemen became a major Western security concern after the Yemen-based regional arm of al Qaeda claimed responsibility for a failed attempt to bomb a U.S.-bound plane in December.
Umar Farouk Abdulmutallab, the Nigerian man suspected of being behind the attack, had visited Yemen to study Arabic and Islam and had had contact with radical U.S.-born Muslim preacher Anwar al-Awlaki, who is based in the impoverished Arab country.
Awlaki was also linked to a U.S. Army psychiatrist who shot dead 13 people at the Fort Hood base in Texas in November.
In February, U.S. counterterrorism officials said U.S. spy agencies believed Awlaki to have played a bigger role than first thought in al Qaeda in the Arabian Peninsula's decision to start launching attacks against U.S. targets.
Mobley had been in Yemen for at least a year, an official told Reuters, first studying Arabic at a language institute in the capital before attending Al-Eman University, which is run by prominent hardline cleric Sheikh Abdul-Majid al-Zindani.
Western allies and neighboring Saudi Arabia fear al Qaeda is exploiting instability in Yemen on many fronts to recruit and train militants for attacks in the region and beyond.
In addition to fighting al Qaeda, Yemen is also struggling to contain separatist tensions in the south where violence has escalated in recent weeks.
Sanaa is also bringing an end to a northern Shi'ite insurgency. Last month, facing international pressure to turn its sights to al Qaeda, Sanaa declared a truce in the long-running northern conflict.
U.S. State Department spokesman P.J. Crowley said: "We have contacted the Yemeni authorities to set up a consular visit to verify the citizenship of a person being detained in Sanaa, but we haven't had that meeting yet."
(Additional reporting by Jeremy Pelofsky in Washington, Writing by Raissa Kasolowsky in Dubai)